From 48d573c2e13904741c9505d513bf5156eab512b8 Mon Sep 17 00:00:00 2001
From: Bruno Ricci <riccibrun@gmail.com>
Date: Tue, 27 Aug 2019 11:35:49 +0000
Subject: [PATCH] [clang] Ensure that statements, expressions and types are
 trivially destructible

Since statements, expressions and types are allocated with the BumpPtrAllocator
from ASTContext their destructor is not executed. Two classes are currently
exempted from the check : InitListExpr due to its ASTVector and
ConstantArrayType due to its APInt.

No functional changes.

Differential Revision: https://reviews.llvm.org/D66646

Reviewed By: lebedev.ri, gribozavr

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@370044 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/AST/Stmt.cpp | 11 +++++++++++
 lib/AST/Type.cpp | 13 +++++++++++++
 2 files changed, 24 insertions(+)

diff --git a/lib/AST/Stmt.cpp b/lib/AST/Stmt.cpp
index 0a4d403106..80a1451ac7 100644
--- a/lib/AST/Stmt.cpp
+++ b/lib/AST/Stmt.cpp
@@ -41,6 +41,7 @@
 #include <cstring>
 #include <string>
 #include <utility>
+#include <type_traits>
 
 using namespace clang;
 
@@ -83,6 +84,16 @@ const char *Stmt::getStmtClassName() const {
                 #CLASS " should not be polymorphic!");
 #include "clang/AST/StmtNodes.inc"
 
+// Check that no statement / expression class has a non-trival destructor.
+// Statements and expressions are allocated with the BumpPtrAllocator from
+// ASTContext and therefore their destructor is not executed.
+#define STMT(CLASS, PARENT)                                                    \
+  static_assert(std::is_trivially_destructible<CLASS>::value,                  \
+                #CLASS " should be trivially destructible!");
+// FIXME: InitListExpr is not trivially destructible due to its ASTVector.
+#define INITLISTEXPR(CLASS, PARENT)
+#include "clang/AST/StmtNodes.inc"
+
 void Stmt::PrintStats() {
   // Ensure the table is primed.
   getStmtInfoTableEntry(Stmt::NullStmtClass);
diff --git a/lib/AST/Type.cpp b/lib/AST/Type.cpp
index 7e08e72f4e..608626820a 100644
--- a/lib/AST/Type.cpp
+++ b/lib/AST/Type.cpp
@@ -50,6 +50,7 @@
 #include <cassert>
 #include <cstdint>
 #include <cstring>
+#include <type_traits>
 
 using namespace clang;
 
@@ -299,6 +300,18 @@ QualType QualType::getSingleStepDesugaredTypeImpl(QualType type,
                 #CLASS "Type should not be polymorphic!");
 #include "clang/AST/TypeNodes.def"
 
+// Check that no type class has a non-trival destructor. Types are
+// allocated with the BumpPtrAllocator from ASTContext and therefore
+// their destructor is not executed.
+//
+// FIXME: ConstantArrayType is not trivially destructible because of its
+// APInt member. It should be replaced in favor of ASTContext allocation.
+#define TYPE(CLASS, BASE)                                                      \
+  static_assert(std::is_trivially_destructible<CLASS##Type>::value ||          \
+                    std::is_same<CLASS##Type, ConstantArrayType>::value,       \
+                #CLASS "Type should be trivially destructible!");
+#include "clang/AST/TypeNodes.def"
+
 QualType Type::getLocallyUnqualifiedSingleStepDesugaredType() const {
   switch (getTypeClass()) {
 #define ABSTRACT_TYPE(Class, Parent)
-- 
2.40.0